iv7

iv7 denotes a subdominant seventh chord built on the fourth scale degree of a key. The roman numeral iv is lowercase to indicate a minor triad, and the appended 7 designates a minor seventh, producing a four-note chord: root, minor third, perfect fifth, and minor seventh. In major keys, iv7 is typically a borrowed chord from the parallel minor; in natural minor, iv7 is diatonic.

Construction and examples: In C major, iv7 is Fm7 (F–Ab–C–Eb). In A minor, iv7 is Dm7 (D–F–A–C) and in D minor, iv7 is Gm7 (G–Bb–D–F).

Function and voice leading: iv7 functions as a predominant chord, often preceding V or i. The presence of the minor seventh adds tension that typically resolves downward toward the third or root of the following chord.

Usage and context: In classical harmony iv7 appears as a borrowed chord from the parallel minor to expand the subdominant area. In jazz and popular music, iv7 is a common color chord and may be extended with tensions (9, 11, 13) or substituted with altered variants; its role remains predominant before V or i.

Notation and variations: The symbol iv7 communicates a minor subdominant seventh; in analyses, it reveals modal interchange in major keys or is diatonic in minor keys depending on the scale used (natural, harmonic, or melodic minor).